Golf ball compositions

ABSTRACT

Disclosed herein are multilayer golf balls having a layer with a higher hardness and a lower flexural modulus than another layer.

FIELD OF THE INVENTION

The present invention relates generally to golf balls comprising a firstlayer having a higher hardness and a lower flexural modulus than asecond layer.

BACKGROUND OF THE INVENTION

For the vast majority of materials, hardness is used synonymously withflexural modulus. Although both hardness and flexural modulus reflecthow a material feels to the touch, hardness measures the resistance toindentation, while flexural modulus measures the resistance to bending.Generally, flexural modulus tends to increase with hardness in apredictable manner, such that the flexural modulus of a material can bepredicted based on the material's hardness. Thus, if a first materialhas a higher hardness than a second material, then the first materialwill typically have a higher flexural modulus than the second material.The present invention provides a novel golf ball construction whereinthe typical hardness/modulus relationship does not exist between two ofthe layers. For example, if the composition used to form a first layerhas a higher hardness than the composition used to form a second layer,then the composition used to form the first layer will have a lowerflexural modulus than the composition used to form the second layer.Such compositions provide unique properties of spin and feel to a golfball.

SUMMARY OF THE INVENTION

In one embodiment, the present invention is directed to a golf ballcomprising a first layer and a second layer, wherein the compositionused to form the first layer has a higher Shore C hardness and a lowerflexural modulus than the composition used to form the second layer.

In another embodiment, the present invention is directed to a golf ballcomprising a solid, single layer core formed from a first composition,an inner cover layer formed from a second composition, and an outercover layer. The first composition has a higher Shore C hardness andlower flexural modulus than the second composition.

In another embodiment, the present invention is directed to a golf ballcomprising an inner core layer, an outer core layer, an inner coverlayer, and an outer cover layer. The composition used to form the outercore layer has a higher Shore C hardness and a lower flexural modulusthan the composition used to form the inner cover layer.

In another embodiment, the present invention is directed to a golf ballcomprising a solid, single layer core formed from a first composition,an inner cover layer formed from a second composition, and an outercover layer. The second composition has a higher Shore C hardness andlower flexural modulus than the first composition.

DETAILED DESCRIPTION

Golf balls of the present invention are multilayer balls (i.e., solidcore of one or more layers and a cover of one or more layers), having anovel construction wherein one layer has a higher hardness and a lowerflexural modulus than that of another layer. Such hardness/modulusrelationship can be achieved by forming the layers from the samematerial and adjusting the material's hardness/modulus to a firstdesirable level for one layer and a second desirable level for anotherlayer (e.g., two polyurethane layers having different isocyanatelevels), or by forming the layers from different materials (e.g., anionomer layer and a rubber layer), wherein each material's hardness isadjusted to the desirable level. Thus, each layer of the ball is formedfrom a composition independently selected from the following thermosetand thermoplastic compositions, so long as the composition used to formone layer has a higher hardness and a lower flexural modulus than thecomposition used to form another layer.

Suitable thermoset compositions include, but are not limited to, naturalrubbers, polybutadienes, polyisoprenes, ethylene propylene rubbers(EPR), ethylene-propylene-diene rubbers (EPDM), styrene-butadienerubbers, butyl rubbers, halobutyl rubbers, polyurethanes, polyureas,acrylonitrile butadiene rubbers, polychloroprenes, alkyl acrylaterubbers, chlorinated isoprene rubbers, acrylonitrile chlorinatedisoprene rubbers, polyalkenamers, phenol formaldehydes, melamineformaldehydes, polyepoxides, polysiloxanes, polyesters, alkyds,polyisocyanurates, polycyanurates, polyacrylates, and combinations oftwo or more thereof.

Suitable initiator agents include organic peroxides, high energyradiation sources capable of generating free radicals, C-C initiators,and combinations thereof. High energy radiation sources capable ofgenerating free radicals include, but are not limited to, electronbeams, ultra-violet radiation, gamma radiation, X-ray radiation,infrared radiation, heat, and combinations thereof. Suitable organicperoxides include, but are not limited to, dicumyl peroxide;n-butyl-4,4-di(t-butylperoxy) valerate;1,1-di(t-butylperoxy)3,3,5-trimethylcyclohexane;2,5-dimethyl-2,5-di(t-butylperoxy) hexane; di-t-butyl peroxide;di-t-amyl peroxide; t-butyl peroxide; t-butyl cumyl peroxide;2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3;di(2-t-butyl-peroxyisopropyl)benzene; dilauroyl peroxide; dibenzoylperoxide; t-butyl hydroperoxide; lauryl peroxide; benzoyl peroxide; andcombinations thereof.

Examples of suitable commercially available peroxides include, but arenot limited to Perkadox® BC dicumyl peroxide, commercially availablefrom Akzo Nobel, and Varox® peroxides, such as Varox® ANS benzoylperoxide and Varox® 231 1,1-di(t-butylperoxy)3,3,5-trimethylcyclohexane,commercially available from RT Vanderbilt Company, Inc. Peroxideinitiator agents are generally present in the thermoset composition inan amount of at least 0.05 parts by weight per 100 parts of the basepolymer, or an amount within the range having a lower limit of 0.05parts or 0.1 parts or 0.8 parts or 1 part or 1.25 parts or 1.5 parts byweight per 100 parts of the base polymer, and an upper limit of 2.5parts or 3 parts or 5 parts or 6 parts or 10 parts or 15 parts by weightper 100 parts of the base polymer.

Coagents are commonly used with peroxides to increase the state of cure.Suitable coagents include, but are not limited to, metal salts ofunsaturated carboxylic acids; unsaturated vinyl compounds andpolyfunctional monomers (e.g., trimethylolpropane trimethacrylate);phenylene bismaleimide; and combinations thereof. Particular examples ofsuitable metal salts include, but are not limited to, one or more metalsalts of acrylates, diacrylates, methacrylates, and dimethacrylates,wherein the metal is selected from magnesium, calcium, zinc, aluminum,lithium, nickel, and sodium. In a particular embodiment, the coagent isselected from zinc salts of acrylates, diacrylates, methacrylates,dimethacrylates, and mixtures thereof. In another particular embodiment,the coagent is zinc diacrylate. When the coagent is zinc diacrylateand/or zinc dimethacrylate, the coagent is typically included in thethermoset composition in an amount within the range having a lower limitof 1 or 5 or 10 or 15 or 19 or 20 parts by weight per 100 parts of thebase polymer, and an upper limit of 24 or 25 or 30 or 35 or 40 or 45 or50 or 60 parts by weight per 100 parts of the base polymer. When one ormore less active coagents are used, such as zinc monomethacrylate andvarious liquid acrylates and methacrylates, the amount of less activecoagent used may be the same as or higher than for zinc diacrylate andzinc dimethacrylate coagents.

The thermoset composition optionally includes a curing agent. Suitablecuring agents include, but are not limited to, sulfur; N-oxydiethylene2-benzothiazole sulfenamide; N,N-di-ortho-tolylguanidine; bismuthdimethyldithiocarbamate; N-cyclohexyl 2-benzothiazole sulfenamide;N,N-diphenylguanidine; 4-morpholinyl-2-benzothiazole disulfide;dipentamethylenethiuram hexasulfide; thiuram disulfides;mercaptobenzothiazoles; sulfenamides; dithiocarbamates; thiuramsulfides; guanidines; thioureas; xanthates; dithiophosphates;aldehyde-amines; dibenzothiazyl disulfide; tetraethylthiuram disulfide;tetrabutylthiuram disulfide; and combinations thereof.

The thermoset composition optionally contains one or more antioxidants.Antioxidants are compounds that can inhibit or prevent the oxidativedegradation of the base polymer. Some antioxidants also act as freeradical scavengers; thus, when antioxidants are included in thethermoset composition, the amount of initiator agent used may be as highor higher than the amounts disclosed herein. Suitable antioxidantsinclude, for example, dihydroquinoline antioxidants, amine typeantioxidants, and phenolic type antioxidants.

The thermoset composition optionally includes a soft and fast agent.Preferably, the thermoset composition contains from 0.05 phr to 10.0 phrof a soft and fast agent. In one embodiment, the soft and fast agent ispresent in an amount within a range having a lower limit of 0.05 or 0.1or 0.2 or 0.5 phr and an upper limit of 1.0 or 2.0 or 3.0 or 5.0 phr. Inanother embodiment, the soft and fast agent is present in an amount offrom 2.0 phr to 5.0 phr, or from 2.35 phr to 4.0 phr, or from 2.35 phrto 3.0 phr.

Suitable soft and fast agents include, but are not limited to,organosulfur and metal-containing organosulfur compounds; organic sulfurcompounds, including mono, di, and polysulfides, thiol, and mercaptocompounds; inorganic sulfide compounds; blends of an organosulfurcompound and an inorganic sulfide compound; Group VIA compounds;substituted and unsubstituted aromatic organic compounds that do notcontain sulfur or metal; aromatic organometallic compounds;hydroquinones; benzoquinones; quinhydrones; catechols; resorcinols; andcombinations thereof. In a particular embodiment, the soft and fastagent is selected from zinc pentachlorothiophenol,pentachlorothiophenol, ditolyl disulfide, diphenyl disulfide, dixylyldisulfide, 2-nitroresorcinol, and combinations thereof.

The thermoset composition may contain one or more fillers. Exemplaryfillers include precipitated hydrated silica, clay, talc, asbestos,glass fibers, aramid fibers, mica, calcium metasilicate, zinc sulfate,barium sulfate, zinc sulfide, lithopone, silicates, silicon carbide,diatomaceous earth, carbonates (e.g., calcium carbonate, zinc carbonate,barium carbonate, and magnesium carbonate), metals (e.g., titanium,tungsten, aluminum, bismuth, nickel, molybdenum, iron, lead, copper,boron, cobalt, beryllium, zinc, and tin), metal alloys (e.g., steel,brass, bronze, boron carbide whiskers, and tungsten carbide whiskers),oxides (e.g., zinc oxide, tin oxide, iron oxide, calcium oxide, aluminumoxide, titanium dioxide, magnesium oxide, and zirconium oxide),particulate carbonaceous materials (e.g., graphite, carbon black, cottonflock, natural bitumen, cellulose flock, and leather fiber),microballoons (e.g., glass and ceramic), fly ash, core material that isground and recycled, nanofillers and combinations thereof.

The thermoset composition may also contain one or more additivesselected from processing aids, such as transpolyisoprene (e.g., TP-301transpolyisoprene, commercially available from Kuraray Co., Ltd.) andtransbutadiene rubber; processing oils; plasticizers; coloring agents;fluorescent agents; chemical blowing and foaming agents; defoamingagents; stabilizers; softening agents; impact modifiers; free radicalscavengers; accelerators; scorch retarders; and the like.

Non-limiting examples of suitable commercially available thermosetrubbers are Buna CB high-cis neodymium-catalyzed polybutadiene rubbers,such as Buna CB 23, and Buna CB high-cis cobalt-catalyzed polybutadienerubbers, such as Buna CB 1220 and 1221, commercially available fromLanxess Corporation; SE BR-1220, commercially available from The DowChemical Company; Europrene® NEOCIS® BR 40 and BR 60, commerciallyavailable from Polimeri Europa®; UBEPOL-BR® rubbers, commerciallyavailable from UBE Industries, Inc.; BR 01, commercially available fromJapan Synthetic Rubber Co., Ltd.; Neodene high-cis neodymium-catalyzedpolybutadiene rubbers, such as Neodene BR 40, commercially availablefrom Karbochem; TP-301 transpolyisoprene, commercially available fromKuraray Co., Ltd.; Vestenamer® polyoctenamer, commercially availablefrom Evonik Industries; Butyl 065 and Butyl 288 butyl rubbers,commercially available from ExxonMobil Chemical Company; Butyl 301 andButyl 101-3, commercially available from Lanxess Corporation; Bromobutyl2224 and Chlorobutyl 1066 halobutyl rubbers, commercially available fromExxonMobil Chemical Company; Bromobutyl X2 and Chlorobutyl 1240halobutyl rubbers, commercially available from Lanxess Corporation;BromoButyl 2255 butyl rubber, commercially available from JapanSynthetic Rubber Co., Ltd.; Vistalon® 404 and Vistalon® 706 ethylenepropylene rubbers, commercially available from ExxonMobil ChemicalCompany; Dutral CO 058 ethylene propylene rubber, commercially availablefrom Polimeri Europa; Nordel® IP NDR 5565 and Nordel® IP 3670ethylene-propylene-diene rubbers, commercially available from The DowChemical Company; EPT1045 and EPT1045 ethylene-propylene-diene rubbers,commercially available from Mitsui Corporation; Buna SE 1721 TEstyrene-butadiene rubbers, commercially available from LanxessCorporation; Afpol 1500 and Afpol 552 styrene-butadiene rubbers,commercially available from Karbochem; Nipol® DN407 and Nipol® 1041Lacrylonitrile butadiene rubbers, commercially available from ZeonChemicals, L.P.; Neoprene GRT and Neoprene AD30 polychloroprene rubbers;Vamac® ethylene acrylic elastomers, commercially available from E. I. duPont de Nemours and Company; Hytemp® AR12 and AR214 alkyl acrylaterubbers, commercially available from Zeon Chemicals, L.P.; and Hypalon®chlorosulfonated polyethylene rubbers, commercially available from E. I.du Pont de Nemours and Company.

Suitable types and amounts of base rubber, initiator agent, coagent,filler, and additives are more fully described in, for example, U.S.Pat. Nos. 6,566,483, 6,695,718, 6,939,907, 7,041,721 and 7,138,460, theentire disclosures of which are hereby incorporated herein by reference.Particularly suitable diene rubber compositions are further disclosed,for example, in U.S. Patent Application Publication No. 2007/0093318,the entire disclosure of which is hereby incorporated herein byreference.

Suitable thermoplastic compositions include, but are not limited to,partially- and fully-neutralized ionomers, graft copolymers of ionomerand polyamide, and the following non-ionomeric polymers, includinghomopolymers and copolymers thereof, as well as their derivatives thatare compatibilized with at least one grafted or copolymerized functionalgroup, such as maleic anhydride, amine, epoxy, isocyanate, hydroxyl,sulfonate, phosphonate, and the like:

-   -   (a) polyesters, particularly those modified with a        compatibilizing group such as sulfonate or phosphonate,        including modified poly(ethylene terephthalate), modified        poly(butylene terephthalate), modified poly(propylene        terephthalate), modified poly(trimethylene terephthalate),        modified poly(ethylene naphthenate), including, but not limited        to, those disclosed in U.S. Pat. Nos. 6,353,050, 6,274,298, and        6,001,930, the entire disclosures of which are hereby        incorporated herein by reference;    -   (b) polyamides, polyamide-ethers, and polyamide-esters,        including, but not limited to, those disclosed in U.S. Pat. Nos.        6,187,864, 6,001,930, and 5,981,654, the entire disclosures of        which are hereby incorporated herein by reference;    -   (c) polyurethanes, polyureas, polyurethane-polyurea hybrids, and        blends of two or more thereof, including, but not limited to,        those disclosed in U.S. Pat. Nos. 5,334,673, 5,484,870,        6,506,851, 6,756,436, 6,835,794, 6,867,279, 6,960,630, and        7,105,623, U.S. Patent Application Publication No. 2007/0117923,        and U.S. Patent Application Ser. Nos. 60/401,047 and 13/613,095,        the entire disclosures of which are hereby incorporated herein        by reference;    -   (d) fluoropolymers, including, but not limited to, those        disclosed in U.S. Pat. Nos. 5,691,066, 6,747,110 and 7,009,002,        the entire disclosures of which are hereby incorporated herein        by reference;    -   (e) non-ionomeric acid polymers, such as O/X- and O/X/Y-type        copolymers, wherein O is an olefin (e.g., ethylene), X is a        carboxylic acid such as acrylic, methacrylic, crotonic, maleic,        fumaric, or itaconic acid, and Y is a softening comonomer such        as vinyl esters of aliphatic carboxylic acids wherein the acid        has from 2 to 10 carbons, alkyl ethers wherein the alkyl group        has from 1 to 10 carbons, and alkyl alkylacrylates such as alkyl        methacrylates wherein the alkyl group has from 1 to 10 carbons;        including, but not limited to, those disclosed in U.S. Pat. No.        6,872,774, the entire disclosure of which is hereby incorporated        herein by reference;    -   (f) metallocene-catalyzed polymers, including, but not limited        to, those disclosed in U.S. Pat. Nos. 6,274,669, 5,919,862,        5,981,654, and 5,703,166, the entire disclosures of which are        hereby incorporated herein by reference;    -   (g) polystyrenes, such as poly(styrene-co-maleic anhydride),        acrylonitrile-butadiene-styrene, poly(styrene sulfonate),        polyethylene styrene;    -   (h) polypropylenes, polyethylenes, propylene elastomers,        ethylene elastomers, copolymers of propylene and ethylene, and        blends of two or more thereof;    -   (i) polyvinyl chlorides, and blends of two or more thereof;    -   (j) polyvinyl acetates, preferably having less than about 9% of        vinyl acetate by weight, and blends of two or more thereof;    -   (k) polycarbonates, blends of        polycarbonate/acrylonitrile-butadiene-styrene, blends of        polycarbonate/polyurethane, blends of polycarbonate/polyester,        and blends of two or more thereof;    -   (l) polyvinyl alcohols, and blends of two or more thereof;    -   (m) polyethers, such as polyarylene ethers, polyphenylene        oxides, block copolymers of alkenyl aromatics with vinyl        aromatics and poly(amic ester)s, and blends of two or more        thereof;    -   (n) polyimides, polyetherketones, polyamideimides, and blends of        two or more thereof;    -   (o) polycarbonate/polyester copolymers and blends of two or more        thereof; and    -   (p) combinations of any two or more of the above thermoplastic        polymers.

Suitable ionomer compositions include partially neutralized ionomers andhighly neutralized ionomers, including ionomers formed from blends oftwo or more partially neutralized ionomers, blends of two or more highlyneutralized ionomers, and blends of one or more partially neutralizedionomers with one or more highly neutralized ionomers. Preferredionomers are salts of O/X- and O/X/Y-type acid copolymers, wherein O isan α-olefin, X is a C₃-C₈ α,β-ethylenically unsaturated carboxylic acid,and Y is a softening monomer. O is preferably selected from ethylene andpropylene. X is preferably selected from methacrylic acid, acrylic acid,ethacrylic acid, crotonic acid, and itaconic acid. Methacrylic acid andacrylic acid are particularly preferred. As used herein, “(meth) acrylicacid” means methacrylic acid and/or acrylic acid. Likewise, “(meth)acrylate” means methacrylate and/or acrylate. Y is preferably selectedfrom (meth) acrylate and alkyl (meth) acrylates wherein the alkyl groupshave from 1 to 8 carbon atoms, including, but not limited to, n-butyl(meth) acrylate, isobutyl (meth) acrylate, methyl (meth) acrylate, andethyl (meth) acrylate. Particularly preferred O/X/Y-type copolymers areethylene/(meth) acrylic acid/n-butyl (meth) acrylate, ethylene/(meth)acrylic acid/isobutyl (meth) acrylate, ethylene/(meth) acrylicacid/methyl (meth) acrylate, and ethylene/(meth) acrylic acid/ethyl(meth) acrylate. The acid is typically present in the acid copolymer inan amount of 6 wt % or greater, or 9 wt % or greater, or 10 wt % orgreater, or 11 wt % or greater, or 15 wt % or greater, or 16 wt % orgreater, or in an amount within a range having a lower limit of 1 or 4or 6 or 8 or 10 or 11 or 12 or 15 wt % and an upper limit of 15 or 16 or17 or 19 or 20 or 20.5 or 21 or 25 or 30 or 35 or 40 wt %, based on thetotal weight of the acid copolymer. The acid copolymer is at leastpartially neutralized with a cation source, optionally in the presenceof a high molecular weight organic acid, such as those disclosed in U.S.Pat. No. 6,756,436, the entire disclosure of which is herebyincorporated herein by reference. In a particular embodiment, less than40% of the acid groups present in the composition are neutralized. Inanother particular embodiment, from 40% to 60% of the acid groupspresent in the composition are neutralized. In another particularembodiment, from 60% to 70% of the acid groups present in thecomposition are neutralized. In another embodiment, 60% to 80% of theacid groups present in the composition are neutralized. In anotherembodiment, from 80% to 100% of the acid groups present in thecomposition are neutralized. Suitable cation sources include, but arenot limited to, metal ion sources, such as compounds of alkali metals,alkaline earth metals, transition metals, and rare earth elements;ammonium salts and monoamine salts; and combinations thereof. Preferredcation sources are compounds of magnesium, sodium, potassium, cesium,calcium, barium, manganese, copper, zinc, tin, lithium, and rare earthmetals. In a particular embodiment, the ionomer composition includes abimodal ionomer, for example, DuPont® AD1043 ionomers, and the ionomersdisclosed in U.S. Patent Application Publication No. 2004/0220343 andU.S. Pat. Nos. 6,562,906, 6,762,246 and 7,273,903, the entiredisclosures of which are hereby incorporated herein by reference.Suitable ionomers are further disclosed, for example, in U.S. PatentApplication Publication Nos. 2005/0049367, 2005/0148725, 2005/0020741,2004/0220343, and 2003/0130434, and U.S. Pat. Nos. 5,587,430, 5,691,418,5,866,658, 6,100,321, 6,562,906, 6,653,382, 6,756,436, 6,777,472,6,762,246, 6,815,480, 6,894,098, 6,919,393, 6,953,820, 6,994,638,7,375,151, and 7,652,086, the entire disclosures of which are herebyincorporated herein by reference.

Also suitable are thermoplastic elastomers comprising a siliconeionomer, as disclosed, for example, in U.S. Pat. No. 8,329,156, theentire disclosure of which is hereby incorporated herein by reference.

The thermoplastic composition may contain additive(s) and/or filler(s)in an amount of 50 wt % or less, or 30 wt % or less, or 20 wt % or less,or 15 wt % or less, based on the total weight of the thermoplasticcomposition. Suitable additives and fillers include, but are not limitedto, chemical blowing and foaming agents, optical brighteners, coloringagents, fluorescent agents, whitening agents, UV absorbers, lightstabilizers, defoaming agents, processing aids, antioxidants,stabilizers, softening agents, fragrance components, plasticizers,impact modifiers, TiO₂, acid copolymer wax, surfactants, performanceadditives (e.g., A-C® performance additives, particularly A-C® lowmolecular weight ionomers and copolymers, A-C® oxidized polyethylenes,A-C® ethylene vinyl acetate waxes, and AClyn® low molecular weightionomers, commercially available from Honeywell International Inc.),fatty acid amides (e.g., ethylene bis-stearamide and ethylenebis-oleamide), fatty acids and salts thereof (e.g., stearic acid, oleicacid, zinc stearate, magnesium stearate, zinc oleate, and magnesiumoleate), oxides (e.g., zinc oxide, tin oxide, iron oxide, calcium oxide,aluminum oxide, titanium dioxide, magnesium oxide, and zirconium oxide),carbonates (e.g., calcium carbonate, zinc carbonate, barium carbonate,and magnesium carbonate), barium sulfate, zinc sulfate, tungsten,tungsten carbide, silica, lead silicate, clay, mica, talc, nano-fillers,carbon black, glass flake, milled glass, flock, fibers, core materialthat is ground and recycled, and mixtures thereof. Suitable additivesand fillers are more fully described in, for example, U.S. PatentApplication Publication No. 2003/0225197, the entire disclosure of whichis hereby incorporated herein by reference. In a particular embodiment,the total amount of additive(s) and filler(s) present in thethermoplastic composition is 20 wt % or less, or 15 wt % or less, or 12wt % or less, or 10 wt % or less, or 9 wt % or less, or 6 wt % or less,or 5 wt % or less, or 4 wt % or less, or 3 wt % or less, or within arange having a lower limit of 0 or 2 or 3 or 5 wt %, based on the totalweight of the thermoset composition, and an upper limit of 9 or 10 or 12or 15 or 20 wt %, based on the total weight of the thermoplasticcomposition. In a particular aspect of this embodiment, thethermoplastic composition includes filler(s) selected from carbon black,micro- and nano-scale clays and organoclays, including (e.g., Cloisite®and Nanofil® nanoclays, commercially available from Southern ClayProducts, Inc.; Nanomax® and Nanomer® nanoclays, commercially availablefrom Nanocor, Inc., and Perkalite® nanoclays, commercially availablefrom Akzo Nobel Polymer Chemicals), micro- and nano-scale talcs (e.g.,Luzenac HAR® high aspect ratio talcs, commercially available fromLuzenac America, Inc.), glass (e.g., glass flake, milled glass,microglass, and glass fibers), micro- and nano-scale mica and mica-basedpigments (e.g., Iriodin® pearl luster pigments, commercially availablefrom The Merck Group), and combinations thereof. Particularly suitablecombinations of fillers include, but are not limited to, micro-scalefiller(s) combined with nano-scale filler(s), and organic filler(s) withinorganic filler(s).

The thermoplastic composition optionally includes one or more melt flowmodifiers. Suitable melt flow modifiers include materials which increasethe melt flow of the composition, as measured using ASTM D-1238,condition E, at 190° C., using a 2160 gram weight. Examples of suitablemelt flow modifiers include, but are not limited to, fatty acids andfatty acid salts, including, but not limited to, those disclosed in U.S.Pat. No. 5,306,760, the entire disclosure of which is herebyincorporated herein by reference; fatty amides and salts thereof;polyhydric alcohols, including, but not limited to, those disclosed inU.S. Pat. No. 7,365,128, and U.S. Patent Application Publication No.2010/0099514, the entire disclosures of which are hereby incorporatedherein by reference; polylactic acids, including, but not limited to,those disclosed in U.S. Pat. No. 7,642,319, the entire disclosure ofwhich is hereby incorporated herein by reference; and the modifiersdisclosed in U.S. Patent Application Publication No. 2010/0099514 and2009/0203469, the entire disclosures of which are hereby incorporatedherein by reference. Flow enhancing additives also include, but are notlimited to, montanic acids, esters of montanic acids and salts thereof,bis-stearoylethylenediamine, mono- and polyalcohol esters such aspentaerythritol tetrastearate, zwitterionic compounds, andmetallocene-catalyzed polyethylene and polypropylene wax, includingmaleic anhydride modified versions thereof, amide waxes and alkylenediamides such as bistearamides. Particularly suitable fatty amidesinclude, but are not limited to, saturated fatty acid monoamides (e.g.,lauramide, palmitamide, arachidamide behenamide, stearamide, and12-hydroxy stearamide); unsaturated fatty acid monoamides (e.g.,oleamide, erucamide, and ricinoleamide); N-substituted fatty acid amides(e.g., N-stearyl stearamide, N-behenyl behenamide, N-stearyl behenamide,N-behenyl stearamide, N-oleyl oleamide, N-oleyl stearamide, N-stearyloleamide, N-stearyl erucamide, erucyl erucamide, and erucyl stearamide,N-oleyl palmitamide, methylol amide (more preferably, methylolstearamide, methylol behenamide); saturated fatty acid bis-amides (e.g.,methylene bis-stearamide, ethylene bis-stearamide, ethylenebis-isostearamide, ethylene bis-hydroxystearamide, ethylenebis-behenamide, hexamethylene bis-stearamide, hexamethylenebis-behenamide, hexamethylene bis-hydroxystearamide, N,N′-distearyladipamide, and N,N′-distearyl sebacamide); unsaturated fatty acidbis-amides (e.g., ethylene bis-oleamide, hexamethylene bis-oleamide,N,N′-dioleyl adipamide, N,N′-dioleyl sebacamide); and saturated andunsaturated fatty acid tetra amides, stearyl erucamide, ethylene bisstearamide and ethylene bis oleamide. Suitable examples of commerciallyavailable fatty amides include, but are not limited to, Kemamide® fattyacids, such as Kemamide® B (behenamide/arachidamide), Kemamide® W40(N,N′-ethylenebisstearamide), Kemamide® P181 (oleyl palmitamide),Kemamide® S (stearamide), Kemamide® U (oleamide), Kemamide® E(erucamide), Kemamide® O (oleamide), Kemamide® W45(N,N′-ethylenebisstearamide), Kenamide® W20 (N,N′-ethylenebisoleamide),Kemamide® E180 (stearyl erucamide), Kemamide® E221 (erucyl erucamide),Kemamide® S180 (stearyl stearamide), Kemamide® 5221 (erucyl stearamide),commercially available from Chemtura Corporation; and Crodamide® fattyamides, such as Crodamide® OR (oleamide), Crodamide® ER (erucamide),Crodamide® SR (stereamide), Crodamide® BR (behenamide), Crodamide® 203(oleyl palmitamide), and Crodamide® 212 (stearyl erucamide),commercially available from Croda Universal Ltd.

Non-limiting examples of suitable commercially available thermoplasticsare Surlyn® ionomers and DuPont® HPF 1000 and HPF 2000 highlyneutralized ionomers, commercially available from E. I. du Pont deNemours and Company; Clarix ® ionomers, commercially available from A.Schulman, Inc.; Iotek® ionomers, commercially available from ExxonMobilChemical Company; Amplify® IO ionomers, commercially available from TheDow Chemical Company; Amplify® GR functional polymers and Amplify® TYfunctional polymers, commercially available from The Dow ChemicalCompany; Fusabond® functionalized polymers, including ethylene vinylacetates, polyethylenes, metallocene- catalyzed polyethylenes, ethylenepropylene rubbers, and polypropylenes, commercially available from E. I.du Pont de Nemours and Company; Exxelor® maleic anhydride graftedpolymers, including high density polyethylene, polypropylene,semi-crystalline ethylene copolymer, amorphous ethylene copolymer,commercially available from ExxonMobil Chemical Company; ExxonMobil® PPseries polypropylene impact copolymers, such as PP7032E3, PP7032KN,PP7033E3, PP7684KN, commercially available from ExxonMobil ChemicalCompany; Vistamaxx® propylene-based elastomers, commercially availablefrom ExxonMobil Chemical Company; Vistalon® EPDM rubbers, commerciallyavailable from ExxonMobil Chemical Company; Exact® plastomers,commercially available from ExxonMobil Chemical Company; Santoprene®thermoplastic vulcanized elastomers, commercially available fromExxonMobil Chemical Company; Nucrel® acid copolymers, commerciallyavailable from E. I. du Pont de Nemours and Company; Escor® acidcopolymers, commercially available from ExxonMobil Chemical Company;Primacor® acid copolymers, commercially available from The Dow ChemicalCompany; Kraton® styrenic block copolymers, commercially available fromKraton Performance Polymers Inc.; Septon® styrenic block copolymers,commercially available from Kuraray Co., Ltd.; Lotader® ethyleneacrylate based polymers, commercially available from Arkema Corporation;Polybond® grafted polyethylenes and polypropylenes, commerciallyavailable from Chemtura Corporation; Royaltuf® chemically modified EPDM,commercially available from Chemtura Corporation; Vestenamer®polyoctenamer, commercially available from Evonik Industries; Pebax®polyether and polyester amides, commercially available from Arkema Inc.;polyester-based thermoplastic elastomers, such as Hytrel® polyesterelastomers, commercially available from E. I. du Pont de Nemours andCompany, and Riteflex® polyester elastomers, commercially available fromTicona; Estane® thermoplastic polyurethanes, commercially available fromThe Lubrizol Corporation; Grivory® polyamides and Grilamid® polyamides,commercially available from EMS Grivory; Zytel® polyamide resins andElvamide® nylon multipolymer resins, commercially available from E. I.du Pont de Nemours and Company; and Elvaloy® acrylate copolymer resins,commercially available from E. I. du Pont de Nemours and Company.

Golf balls of the present invention have at least one layer with ahigher hardness and a lower flexural modulus than that of another layer.For purposes of the present disclosure, such a layer having an atypicalrelative hardness/modulus relationship with at least one other layer ofthe ball is referred to herein as an atypical hardness/modulus layer. Ina particular embodiment, the golf ball includes an atypicalhardness/modulus layer formed from a soft and stiff composition, asdisclosed in U.S. Patent Application Publication Nos. 2012/0115633 and2012/0115640, the entire disclosures of which are hereby incorporatedherein by reference, and/or an atypical hardness/modulus layer formedfrom a hard and flexible composition, as disclosed in U.S. PatentApplication Publication Nos. 2012/0115634 and 2012/0115635, the entiredisclosures of which are hereby incorporated herein by reference.

For purposes of the present invention, a first layer has a higherhardness than a second layer if the Shore C hardness of the first layeris at least 1 Shore C unit greater than the Shore C hardness of thesecond layer. In a particular embodiment, the Shore C hardness of thefirst layer is at least 2 Shore C units, or at least 3 Shore C units, orat least 5 Shore C units, or at least 7 Shore C units, or at least 8Shore C units, or at least 10 Shore C units, or at least 12 Shore Cunits, or at least 15 Shore C units, or at least 20 Shore C unitsgreater than the Shore C hardness of the second layer. For purposes ofthe present invention, a first layer has a lower flexural modulus than asecond layer if the flexural modulus of the first layer is at least 1ksi unit or less than the flexural modulus of the second layer. In aparticular embodiment, the flexural modulus of the first layer is atleast 2 ksi units, or at least 3 ksi units, or at least 5 ksi units, orat least 7 ksi units, or at least 8 ksi units, or at least 10 ksi units,or at least 12 ksi units, or at least 15 ksi units, or at least 20 ksiunits less than the flexural modulus of the second layer.

In a particular embodiment, the golf ball includes a solid, single layercore and a single cover layer. In a particular aspect of thisembodiment, the core has a higher hardness and a lower flexural modulusthan that of the cover, and, optionally, the core has a Shore C hardnessof 86 or greater, or greater than 86, and a flexural modulus of 40 kpsior less, or less than 40 kpsi, or 35 kpsi or less, or less than 35 kpsiand/or the cover layer has a Shore C hardness of 86 or less, or lessthan 86 and a flexural modulus of 41 kpsi or greater, or greater than 41kpsi, or 45 kpsi or greater, or greater than 45 kpsi. In anotherparticular aspect of this embodiment, the core has a lower Shore Chardness and a higher flexural modulus than that of the cover, and,optionally, the core has a Shore C hardness of 88 or less, or less than88, and a flexural modulus of 41 kpsi or greater, or greater than 41kpsi, or 45 kpsi or greater, or greater than 45 kpsi, and/or the coverlayer has a Shore C hardness of 88 or greater, or greater than 88, and aflexural modulus of 40 kpsi or less, or less than 40 kpsi, or 35 kpsi orless, or less than 35 kpsi.

In another particular embodiment, the golf ball includes a solid, singlelayer core, an inner cover layer, and an outer cover layer. In aparticular aspect of this embodiment, the core has a higher hardness anda lower flexural modulus than the inner cover layer, and, optionally,the core has a Shore C hardness of 86 or greater, or greater than 86,and a flexural modulus of 40 kpsi or less, or less than 40 kpsi, or 35kpsi or less, or less than 35 kpsi, and/or the inner cover layer has aShore C hardness of 86 or less, or less than 86 and a flexural modulusof 41 kpsi or greater, or greater than 41 kpsi, or 45 kpsi or greater,or greater than 45 kpsi. The inner cover layer is optionally formed froma composition comprising an ionomer and a functionalized polyethylene,and optionally comprising one or more of an additional ionomer, anadditional functionalized polyethylene, or a filler, such as talc, in anamount of from 5 to 30 wt %, based on the total weight of the innercover layer composition. In another particular aspect of thisembodiment, the core has a lower hardness and a higher flexural modulusthan the inner cover layer, and, optionally, the core has a Shore Chardness of 88 or less, or less than 88, and a flexural modulus of 41kpsi or greater, or greater than 41 kpsi, or 45 kpsi or greater, orgreater than 45 kpsi, and/or the inner cover layer has a Shore Chardness of 88 or greater, or greater than 88, and a flexural modulus of40 kpsi or less, or less than 40 kpsi, or 35 kpsi or less, or less than35 kpsi. The core is optionally formed from a composition comprising anionomer and a functionalized polyethylene, and optionally comprising oneor more of an additional ionomer, an additional functionalizedpolyethylene, or a filler, such as talc, in an amount of from 5 to 30 wt%, based on the total weight of the core composition.

In another particular embodiment, the golf ball includes an inner corelayer, an outer core layer, an inner cover layer, and an outer coverlayer. In a particular aspect of this embodiment, the outer core layerhas a higher hardness and a lower flexural modulus than the inner coverlayer, and, optionally, the outer core layer has a Shore C hardness of86 or greater, or greater than 86, and a flexural modulus of 40 kpsi orless, or less than 40 kpsi, or 35 kpsi or less, or less than 35 kpsi,and/or the inner cover layer has a Shore C hardness of 86 or less, orless than 86 and a flexural modulus of 41 kpsi or greater, or greaterthan 41 kpsi, or 45 kpsi or greater, or greater than 45 kpsi. The innercover layer is optionally formed from a composition comprising anionomer and a functionalized polyethylene, and optionally comprising oneor more of an additional ionomer, an additional functionalizedpolyethylene, or a filler, such as talc, in an amount of from 5 to 30 wt%, based on the total weight of the inner cover layer composition. Inanother particular aspect of this embodiment, the outer core layer has alower Shore C hardness and a higher flexural modulus than the innercover layer, and, optionally, the outer core layer has a Shore Chardness of 88 or less, or less than 88, and a flexural modulus of 41kpsi or greater, or greater than 41 kpsi, or 45 kpsi or greater, orgreater than 45 kpsi, and/or the inner cover layer has a Shore Chardness of 88 or greater, or greater than 88, and a flexural modulus of40 kpsi or less, or less than 40 kpsi, or 35 kpsi or less, or less than35 kpsi. The outer core layer is optionally formed from a compositioncomprising an ionomer and a functionalized polyethylene, and optionallycomprising one or more of an additional ionomer, an additionalfunctionalized polyethylene, or a filler, such as talc, in an amount offrom 5 to 30 wt %, based on the total weight of the outer core layercomposition.

Golf balls of the present invention are typically finished by applyingone or more finishing coats over the cover. For example, a primer and atopcoat may be applied. Either or both of the primer and topcoatcompositions may be pigmented or clear. Several coats of clear orpigmented coatings may be applied.

Primer compositions are typically a solvent-borne or water-bornematerial, particularly selected from, but not limited to, polyurethanes,polyureas, acrylic polyurethanes, polyesters, polyester acrylics, andepoxies. In a particular embodiment, the primer composition is atwo-part solvent-borne polyurethane comprising a resin component and anisocyanate component. In a particular aspect of this embodiment, theisocyanate component is present in an amount of from 31 parts to 35parts, by weight per 100 parts of the resin component. In anotherparticular aspect of this embodiment, the resin component comprises from50 to 58 wt % solids and the isocyanate component comprises from 46 to53 wt % solids.

Topcoat compositions are typically a solvent-borne material particularlyselected from, but not limited to, polyurethanes, polyureas, acrylicpolyurethanes, polyesters, polyester acrylics, and epoxies. In aparticular embodiment, the topcoat composition is a two-partsolvent-borne polyurethane comprising a resin component and anisocyanate component. In a particular aspect of this embodiment, theisocyanate component is present in an amount of from 68 parts to 71parts, by weight per 100 parts of the resin component. In anotherparticular aspect of this embodiment, the resin component comprises from46 to 52 wt % solids and the isocyanate component comprises from 46 to53 wt % solids.

Primer and topcoat compositions optionally include additives including,but not limited to, pigments, tints, dyes, fillers, reaction enhancersor catalysts, crosslinking agents, optical brighteners, propylenecarbonates, such as those disclosed in U.S. Pat. No. 5,840,788, which isincorporated in its entirety by reference herein, coloring agents,fluorescent agents, whitening agents, UV absorbers, hindered amine lightstabilizers, defoaming agents, processing aids, mica, talc,nano-fillers, wetting agents, solvents, and other conventionaladditives. Non-limiting examples of suitable coatings are furtherdisclosed, for example, in U.S. Pat. Nos. 5,409,233; 5,459,220;5,494,291; 5,820,491; 5,669,831; 5,817,735; and 7,935,421, the entiredisclosure of which are hereby incorporated herein by reference.

In a particular embodiment, golf balls of the present invention compriseat least one coat of primer and at least one coat of topcoat. In aparticular aspect of this embodiment, the primer is a solvent-bornecomposition and the topcoat is a solvent-borne composition.

Dimensions of golf ball components, i.e., thickness and diameter, mayvary depending on the desired properties.

Golf ball cores of the present invention include single, dual, andmultilayer cores, and preferably have an overall diameter within therange having a lower limit of 0.75 inches or 1 inch or 1.25 inches or1.4 inches and an upper limit of 1.55 inches or 1.6 inches or 1.62inches or 1.63 inches.

In a particular embodiment, the core is a solid, single layer having adiameter within a range having a lower limit of 0.750 or 1.00 or 1.10 or1.15 or 1.20 or 1.25 or 1.30 or 1.40 or 1.50 or 1.53 or 1.55 inches andan upper limit of 1.55 or 1.60 or 1.62 or 1.63 or 1.65 inches. In aparticular aspect of this embodiment, the core has a compression of 90or less, or 80 or less, or 75 or less, or 70 or less, or a compressionwithin a range having a lower limit of 50 or 55 or 60 or 65 and an upperlimit of 65 or 70 or 75 or 80 or 90.

In another particular embodiment, the core comprises an inner core layerand an outer core layer, the inner core layer having a diameter within arange having a lower limit of 0.900 or 0.910 or 0.920 or 0.930 or 0.940or 0.950 or 0.960 or 0.970 or 0.980 or 0.990 or 1.000 or 1.010 or 1.020inches and an upper limit of 1.020 or 1.030 or 1.040 or 1.050 or 1.060or 1.070 or 1.080 or 1.090 or 1.100 or 0.110 or 1.120 or 1.130 inches,and the outer core having a thickness within the range having a lowerlimit of 0.050 or 0.100 or 0.200 or 0.250 inches and an upper limit of0.280 or 0.310 or 0.440 or 0.500 inches. In a particular aspect of thisembodiment, the core has an overall dual core compression within a rangehaving a lower limit of 60 or 70 or 80 or 85 and an upper limit of 85 or90 or 95.

Golf ball covers of the present invention include single, dual, andmultilayer covers, and preferably have an overall thickness within therange having a lower limit of 0.03 inches or 0.04 inches or 0.045 inchesor 0.05 inches or 0.06 inches and an upper limit of 0.07 inches or 0.08inches or 0.09 inches or 0.10 inches. Dual and multilayer covers have aninner cover layer and an outer cover layer, and multilayer coversadditionally have at least one intermediate cover layer disposed betweenthe inner cover layer and the outer cover layer. In a particularembodiment, the cover is a single layer having a thickness within arange having a lower limit of 0.020 or 0.025 or 0.030 inches and anupper limit of 0.030 or 0.040 or 0.045 or 0.050 or 0.070 or 0.100 or0.120 or 0.150 or 0.350 or 0.400 or inches. In another particularembodiment, the cover comprises an inner cover layer and an outer coverlayer, the inner cover having a thickness within a range having a lowerlimit of 0.020 or 0.025 or 0.030 or 0.035 inches and an upper limit of0.035 or 0.040 or 0.045 or 0.050 or 0.100 inches, and the outer coverhaving a thickness within a range having a lower limit of 0.020 or 0.025or 0.030 inches and an upper limit of 0.035 or 0.040 or 0.045 inches.

The present invention is not limited by any particular dimple pattern,dimple plan shape, dimple cross-sectional profile, or dimple size.Examples of suitable dimple patterns include, but are not limited to,phyllotaxis-based patterns; polyhedron-based patterns; and patternsbased on multiple copies of one or more irregular domain(s) as disclosedin U.S. Pat. No. 8,029,388, the entire disclosure of which is herebyincorporated herein by reference; and particularly dimple patternssuitable for packing dimples on seamless golf balls. Non-limitingexamples of suitable dimple patterns are further disclosed in U.S. Pat.Nos. 7,927,234, 7,887,439, 7,503,856, 7,258,632, 7,179,178, 6,969,327,6,702,696, 6,699,143, 6,533,684, 6,338,684, 5,842,937, 5,562,552,5,575,477, 5,957,787, 5,249,804, 5,060,953, 4,960,283, and 4,925,193,and U.S. Patent Application Publication Nos. 2006/0025245, 2011/0021292,2011/0165968, and 2011/0183778, the entire disclosures of which arehereby incorporated herein by reference. Non-limiting examples ofseamless golf balls and methods of producing such are further disclosed,for example, in U.S. Pat. Nos. 6,849,007 and 7,422,529, the entiredisclosures of which are hereby incorporated herein by reference. In aparticular embodiment, the dimple pattern is based on a sphericallytiled tetrahedron. The dimples may have a variety of shapes and sizesincluding different depths and perimeters. In particular, the dimplesmay be concave hemispheres, or they may be triangular, square,hexagonal, catenary, polygonal or any other shape known to those skilledin the art. They may also have a cross-sectional profile based on anyknown dimple profile shape including, but not limited to, paraboliccurves, ellipses, spherical curves, saucer-shapes, sine curves,truncated cones, flattened trapezoids, and catenary curves.

Golf balls of the present invention typically have a dimple count withina limit having a lower limit of 250 and an upper limit of 350 or 400 or450 or 500. In a particular embodiment, the dimple count is 252 or 272or 302 or 312 or 320 or 328 or 332 or 336 or 340 or 352 or 360 or 362 or364 or 372 or 376 or 384 or 390 or 392 or 432.

For purposes of the present disclosure, the hardness of a thermoplasticcomposition or a thermoplastic golf ball layer is measured according tothe following procedure. Hardness buttons of the composition (or layer)are compression molded under sufficient temperature and pressure for asufficient amount of time to produce void- and defect-free parts. Thebuttons are surface ground soon after the part reaches room temperatureafter demolding, to produce smooth, flat and parallel surfaces. Thefinished buttons are approximately 1.25 inches in diameter and at least6 mm in thickness. The buttons are then aged for 10 days at 23° C. in adessicator before testing. Hardness measurements are then made pursuantto ASTM D-2240 and/or JIS C (K6301 Type) using a calibrated, digitaldurometer, capable of reading to 0.1 hardness units and set to recordthe maximum hardness reading for each measurement. The digital durometermust be attached to, and its foot made parallel to, the base of anautomatic stand having a travel speed of approximately 25 mm/sec.

For purposes of the present disclosure, the hardness of a thermosetcomposition refers to the surface hardness of a molded 1.55 inchdiameter sphere of the composition. Similarly, the hardness of athermoset golf ball layer refers to the surface hardness of a sphere, asmeasured on the golf ball layer. The surface hardness of a sphere isobtained from the average of a number of measurements taken fromopposing hemispheres, taking care to avoid making measurements on theparting line of the sphere or on surface defects, such as holes orprotrusions. Hardness measurements are made pursuant to ASTM D-2240 andJIS C (K6301 Type) using a calibrated, digital durometer, capable ofreading to 0.1 hardness units and set to record the maximum hardnessreading for each measurement. Because of the curved surface, care mustbe taken to insure that the sphere is centered under the durometerindentor before a surface hardness reading is obtained. The digitaldurometer must be attached to, and its foot made parallel to, the baseof an automatic stand having a travel speed of approximately 25 mm/sec.

For purposes of the present disclosure, the compression of a sphere isdetermined according to a known procedure, using a digital Atticompression test device, wherein a piston is used to compress a sphereagainst a spring. Conversion from Atti compression to Riehle (cores),Riehle (balls), 100 kg deflection, 130-10 kg deflection or effectivemodulus can be carried out according to the formulas given in JeffDalton's Compression by Any Other Name, Science and Golf IV, Proceedingsof the World Scientific Congress of Golf (Eric Thain ed., Routledge,2002).

When numerical lower limits and numerical upper limits are set forthherein, it is contemplated that any combination of these values may beused.

All patents, publications, test procedures, and other references citedherein, including priority documents, are fully incorporated byreference to the extent such disclosure is not inconsistent with thisinvention and for all jurisdictions in which such incorporation ispermitted.

While the illustrative embodiments of the invention have been describedwith particularity, it will be understood that various othermodifications will be apparent to and can be readily made by those ofordinary skill in the art without departing from the spirit and scope ofthe invention. Accordingly, it is not intended that the scope of theclaims appended hereto be limited to the examples and descriptions setforth herein, but rather that the claims be construed as encompassingall of the features of patentable novelty which reside in the presentinvention, including all features which would be treated as equivalentsthereof by those of ordinary skill in the art to which the inventionpertains.

What is claimed is:
 1. A golf ball comprising: a first layer formed froma first composition and a second layer formed from a second composition,wherein the Shore C hardness of the first composition is greater thanthe Shore C hardness of the second composition, and wherein the flexuralmodulus of the first composition is less than the flexural modulus ofthe second composition.
 2. The golf ball of claim 1, wherein the firstcomposition has a Shore C hardness of 86 or greater.
 3. The golf ball ofclaim 1, wherein the first composition has a flexural modulus of 40 ksior less.
 4. The golf ball of claim 1, wherein the second composition hasa Shore C hardness of 86 or less.
 5. The golf ball of claim 1, whereinthe second composition has a flexural modulus of 41 ksi or greater.
 6. Agolf ball comprising: a solid, single layer core formed from a firstcomposition, an inner cover layer formed from a second composition, andan outer cover layer, wherein the first composition has a higher Shore Chardness than the second composition, and wherein the first compositionhas a lower flexural modulus than the second composition.
 7. The golfball of claim 6, wherein the first composition has a Shore C hardness of86 or greater.
 8. The golf ball of claim 6, wherein the firstcomposition has a flexural modulus of 40 ksi or less.
 9. The golf ballof claim 6, wherein the second composition has a Shore C hardness of 86or less.
 10. The golf ball of claim 6, wherein the second compositionhas a flexural modulus of 41 ksi or greater.
 11. A golf ball comprising:an inner core layer, an outer core layer, an inner cover layer, and anouter cover layer; wherein the composition used to form the outer corelayer has a higher Shore C hardness than the composition used to formthe inner cover layer; and wherein the composition used to form theouter core layer has a lower flexural modulus than the composition usedto form the inner cover layer.
 12. The golf ball of claim 11, whereinthe outer core layer composition has a Shore C hardness of 86 orgreater.
 13. The golf ball of claim 11, wherein the outer core layercomposition has a flexural modulus of 46 ksi or less.
 14. The golf ballof claim 11, wherein the inner cover layer composition has a Shore Chardness of 86 or less.
 15. The golf ball of claim 11, wherein the innercover layer composition has a flexural modulus of 48 ksi or greater. 16.A golf ball comprising: a solid, single layer core formed from a firstcomposition, an inner cover layer formed from a second composition, andan outer cover layer, wherein the second composition has a higher ShoreC hardness than the first composition, and wherein the secondcomposition has a lower flexural modulus than the first composition. 17.The golf ball of claim 16, wherein the first composition has a Shore Chardness of 86 or less.
 18. The golf ball of claim 16, wherein the firstcomposition has a flexural modulus of 41 ksi or greater.
 19. The golfball of claim 16, wherein the second composition has a Shore C hardnessof 86 or greater.
 20. The golf ball of claim 16, wherein the secondcomposition has a flexural modulus of 40 ksi or less.